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The evolution of virtual reality (VR) technologies requires setting boundaries of its use. In this study, 3 female participants were experiencing VR scenarios with stressful content and their activity of the autonomic nervous system and EEG were recorded. It has been discovered that virtual reality can evoke acute stress reactions accompanied by activation of the sympathetic nervous system and a decrease in the activity of the parasympathetic nervous system. The high-stress response is accompanied by a decrease in the power of the EEG, and, on the contrary, the activation of the avoidance reaction is accompanied by an increase in the power of the EEG alpha waves. Therefore, the use of stressful VR content can cause high emotional stress to a user and restrictions should be considered.

The perspective of perceiving one’s action affects its speed and accuracy. In the present study, we investigated the change in accuracy and kinematics when subjects throw darts from the first-person perspective and the third-person perspective with varying angles of view. To model the third-person perspective, subjects were looking at themselves as well as the scene through the virtual reality head-mounted display (VR HMD). The scene was supplied by a video feed from the camera located to the up and 0, 20 and 40 degrees to the right behind the subjects. The 28 subjects wore a motion capture suit to register their right hand displacement, velocity and acceleration, as well as torso rotation during the dart throws. The results indicated that mean accuracy shifted in opposite direction with the changes of camera location in vertical axis and in congruent direction in horizontal axis. Kinematic data revealed a smaller angle of torso rotation to the left in all third-person perspective conditions before and during the throw. The amplitude, speed and acceleration in third-person condition were lower compared to the first-person view condition, before the peak velocity of the hand in the direction toward the target and after the peak velocity in lowering the hand. Moreover, the hand movement angle was smaller in the third-person perspective conditions with 20 and 40 angle of view, compared with the first-person perspective condition just preceding the time of peak velocity, and the difference between conditions predicted the changes in mean accuracy of the throws. Thus, the results of this study revealed that subject’s localization contributed to the transformation of the motor program.

Eye-hand coordination during dart throwing includes both the sensory and motor components, as well as cognitive variables, for example, the direction of the subject’s attention to the target or to the hand kinematic. In the present study, subjects performed dart throws in the eyes-open and eyes-closed conditions with simultaneous recording of the kinematics of the throwing hand. The results showed that the position of the hand in its raising phase was closer to the torso when performing more accurate throws with the eyes-open condition compared to more peripheral throws and throws performed in the eyes-closed condition. Following the dart release, the position of the hand in the eyes-open condition was lower compared to the eyes-closed condition. Additionally, in the eyes-closed condition, raising the hand in its backward moving phase negatively predicts the throwing accuracy. Thus, the early phase of the movement is associated with attention, and the final phase is associated with the visual feedback about the throwing accuracy. Raising the hand in the eyes-closed condition reflects an increase in muscle tension, which leads to a decrease in the accuracy of movement. The results of the study can be applied in sports and in the treatment of hand-eye-coordination disorders.

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